Pillow block



7 Sept. 7, 1965 c. HILTON PILLOW BLOCK Filed April 16, 1962 ZNVENTOR.CAR L Hu 'ro- United States Patent 3,205,027 PILLOW BLOCK Carl Hilton,Chicago, 111., assignor, by mesne assignments, to Masten Corporation,Chicago, Ill., a corporation of Illinois Filed Apr. 16, 1962, Ser. No.187,899 3 Claims. (Cl. 308-72) This invention relates to the productionof a novel pillow block.

More particularly the present invention relates to a new and improvedself-aligning pillow block.

It is a particular object of the present invention to provide a novelone-piece pillow block wherein the bearing is non-rotatably butpivotally retained therein whereby self-aligning bearings are providedfor journaling the ends of a rotatable shaft.

In general, the unit of the present invention comprises an inner bearingmember of elastic material such as sintered powdered metal having aspherical outer diameter and a cylindrical inner diameter or bore. Thespherical outside diameter of the bearing is substantially enclosed by arigid one-piece metal housing cast thereabout. The spherical outerdiameter of the bearing permits it to pivot within the rigid housing toallow for alignment of a shaft journaled in the bearing.

Large scale commercial production of a unit of the foregoing type hasbeen restricted at the present time, the basic problem therein beingcasting of a movable spherical insert into a rigid housing and tocompensate for the contraction of the housing on cooling. Without somemethod of compensating for this contraction the insert is locked inplace and as a result cannot be pivoted. One method for compensating forthis contraction is to coat the insert with some material such as alubricant which will be dissipated either in the casting process orafterward. The prime reason for making the latter impractical forconsistent large scale commercial production is that of maintaining auniform coating on the insert and controlling the dissipation of thecoating. Another disadvantage of the aforesaid method is that whensufficient coating is obtained for subsequent pivoting of the insert,some means must be introduced to keep the insert from spinning on itsaxis.

The difiiculties of the prior practices are overcome by the presentinvention which employs a pre-formed bearing composed of elasticmaterial such as the aforesaid porous sintered powdered metalcomposition. Such porous sintered powdered metal material is elasticwithin limits and has properties of expansion and contraction and a highdegree of elasticity, which properties are taken advantage of in thepresent invention.

Other objects and advantages of the present invention together with itsdetails of construction, arrangement of parts and economies thereof willbe apparent from a consideration of the following specification andaccompanying drawings, wherein:

FIG. 1 is a perspective view of a unitary pillow block formed inaccordance with the present invention, and wherein a bearing of thecharacter aforesaid is pivotally disposed and retained within aone-piece metal housing cast thereabout, the housing being of thetwo-bolt flange mounting type.

FIG. 2 is a side elevational view of a bearing employing the presentinvention.

FIG. 3 is an end elevational view thereof.

FIG. 4 is an enlarged transverse fragmentary sectional view of theassembly of FIG. 1.

FIG. 5 is a similar view illustrating the method and means of causingthe bearing to be pivotally disposed within the housing component of theself-aligning pillow block of the present invention.

11 and the cast face of the housing bore.

3,205,027 Patented Sept. 7, 1965 ice Referring to the drawings, thereference numeral 10 generally indicates a one-piece metal housing, forexample, aluminum, cast about the bearing generally indicated as 11. Thehousing is formed with a pair of flanges 12, 12 each having a hole 13for reception of a mounting bolt.

It will, of course, be understood that the illustrated pillow block unitis for the purpose of illustration and not limitation; Thus, forexample, the housing may have a threebolt flange mounting and in lieu ofthe axis of the bearing 11 being parallel to the axes of the bolt holes13, 13, it will be understood that the unit may be in the form of thestandard mounting wherein the axes of the bolt holes 13, 13 areperpendicular to the axis of the bearing 11. Of course, the flanges 12,12 are then at an angle of 90 to that shown in the illustration ofFIG. 1. Alternatively the housing may be formed without attachmentflanges so that the outer surface of the portion which embraces hearing11 is cylindrical and is later pressed into a cyclindrical holder by theuser.

The bearing 11, as employed in the present invention, is pre-formed ofconventional powdered metals, typical compositions of which are 90%copper and 10% tin; 77.5% copper, 7.5% tin and 15% lead; 25% copper andiron; 20% copper, 79.5% iron, and 0.5% carbon, and the like. A furtheralternative can be straight iron. These compositions are given for thepurpose of illustration and not limitation. The bearings are composed ofcompressed powders which are sintered in conventional manner to resultin compositions having a resilient spongelike character. These areconventionally employed for self-lubricating bearings in that they areporous and can contain approximately 25% of lubricating oil by volumestored in the tiny interconnected pores of the pie-formed bearing, thistype being known as Oilite bearings.

As shown in for example FIG. 2, the bearing 11 is formed initially witha cylindrical bore 14 and a spherical outer surface 15.

The spherical outer surface 15 of the bearing is, how ever, furtherformed with or medially interrupted by a flat annular surface areacomponent 16. In casting the housing 10 about the bearing 11 in asuitable mold or die, not shown, the bearing 11 is first seated on acore pin and then the one-piece housing 10 is cast thereabout. As aresult, the housing 10 is formed with a mating spherical surface bore17, the medial portion of which is likewise formed with a flat area orband 18 corresponding to the flat area 16 on hearing 11. Desirably alsofor facility in subsequent pivoting, as will be explained, the diameterof the spherical seat 16 of the housing 10 is less than that of thespherical segment surface 15 of the bearing 11.

The housing metal as it cools, shrinks tightly around the bearing 11. Itwill be understood that no coating has been employed between the outersurface of the bearing The bearing 11 as employed in the practice of thepresent invention is initially dry during casting, and subsequentlyimpregnated with oil. Thus, when the assembly as shown in FIG. 4 isremoved from the die, the housing 10 snugly embraces the bearing 11.

In order to result in the bearing 11 being pivotally disposed in thehousing 10, in accordance with the practice of the present invention, Iinsert an arbor 19 within the bore 14 of the bearing 11 and causerelative movement of the two so as to forcibly pivot the bearing 11through an are as illustrated in FIG. 5. As the bearing 11 is forced topivot within the housing 10, the flat surface 18 of the housing 10,being of smaller diameter than the spherical diameter of the bearing 11at the surfaces 15 thereof, causes compression and peening of theresilient and compressible bearing 11, particularly at the conjugationof the spherical and fiat surface components thereof, to cause permanentdeformation thereat since the bearing 11 has a lower compressivestrength than the housing 10. This results in an adequate freeing orseparation of the two so that the bearing 11 is pivotally retainedwithin the housing 10. However, this degree of separation is very small.Separation occurs in the area of interference, about 60% of the centersection of the hearing. The remaining 20% at each end suppliessufficient friction to resist spinning of the insert on its axis.

Thus, the device of the present invention provides a self-aligningbearing surface with a simple means by fastening the bearing to asuitable support and eliminates the need for costly alignment since theunique construction and arrangement of the parts automatically providesfor self-alignment and the assembly relieves undue stress of the engagedrotating shaft in the bearing through application of a ball-joint-likeunit.

Although I have shown and described the preferred embodiment of myself-aligning pillow block and preferred method and means for formingthe same, it will be understood by those skilled in the art that variouschanges may be made in the details thereof Without departing from thespirit and scope of my invention as comprehended by the followingclaims.

I claim:

1. A pillow block comprising a one-piece rigid housing formed with aspherical bore medially interrupted by a fiat annular surface areacomponent, and a bearing composed of elastic material and formed with acylindrical axial bore and having a substantially spherical outersurface snugly and pivotally disposed in and embraced by the defines ofsaid substantially spherical bore.

2. A pillow block comprising a one-piece rigid housing formed with aspherical bore medially interrupted by 4 a fiat annular surface areacomponent, and a bearing composed of elastic sintered powdered metalmaterial and formed with a cylindrical axial bore and having acompressed spherical outer surface conforming substantially to that ofsaid first bore and snugly and pivotally disposed in and embraced by thedefines of said first bore.

3. A self-aligning pillow block comprising a one-piece rigid cast metalbearing block formed with a substantially spherical bore mediallyinterrupted by a flat annular surface area component, and a bearingcomposed of porous sintered powdered metal formed with a cylindricalaxial bore and having a compressed spherical outer surface conformingsubstantially to that of said first bore and of greater segment thanthat of said spherical bore snugly and pivotally disposed in andembraced by the defines of said spherical bore, said bearing beingfrictionally retained against spinning on its axis within said housing.

References Cited by the Examiner UNITED STATES PATENTS 1,664,189 3/28Claus 30872 1,684,984 9/28 Claus.

1,693,748 12/28 Fiegel et al.

2,272,118 2/42 Imse 3O8--72 2,724,172 11/55 Potter.

2,796,304 6/57 Downs 308-72 2,919,150 12/59 Baker.

3,004,803 10/61 Irwin 308-72 FOREIGN PATENTS 535,381 4/41 Great Britain.

ROBERT C. RIORDON, Primary Examiner.

WHITMORE A. WILTZ, Examiner.

1. A PILLOW BLOCK COMPRISING A ONE-PIECE RIGID HOUSING FORM WITH ASPHERICAL BORE MEDIALLY INTERRUPTED BY A FLAT ANNULAR SURFACE AREACOMPONENT, AND A BEARING COMPOSED OF ELASTIC MATERIAL AND FORMED WITH ACYLINDRICAL AXIAL BORE AND HAVING A SUBSTANTIALLY SPHERICAL OUTER SUR-